Fig. 1

Evi1^TO mouse model for 3q26-rearranged myeloid malignancies. a Schematic diagram of the Neo-Stop-Tet Operon (NSTO) construct from Tanaka et al.⁶³ that was inserted into the endogenous Evi1 locus by homologous recombination. The construct consists of a neomycin resistance gene and transcriptional Stop cassette flanked by FRT sites, followed by seven Tet operons in succession and a minimal CMV promoter. Following homologous recombination in embryonic stem cells, the Neo-STOP cassette was removed by induction of flpE recombinase. Black triangles represent FRT sites, and white triangles represent loxP sites. b Reverse transcription-quantitative polymerase chain reaction (RT-qPCR) analysis of RNA from cultured leukemic cell lines bearing a provirally-activated EVI1 allele (left-hand columns), or RNA from mouse tissues from wild-type (kidney, an organ with relatively high levels of expression of both Evi1 and Mds1-Evi1⁶⁸), and from DOX-induced Evi1^TO, Rosa26^rtTA mice. Shown is quantitation of Evi1 and Mds1-Evi1 transcripts. Data is normalized to EVI1 RNA levels in WT bone marrow; log₁₀ scale. c Schematic of competitive transplant long-term induction model. CD45.2 whole bone marrow from either Evi1^TO or a WT control with the indicated genotypes was mixed at a 1:1 ratio with WT UBC-GFP-positive bone marrow and transplanted into lethally irradiated recipient mice. Mice were placed on DOX chow at 4 weeks post transplant and analyzed 2, 6, or 10 weeks post induction. Long-term induction experiment was done twice (set A, n = 24, set B, n = 24). Each time point of each set had 8 mice (WT, n = 4, EVI1, n = 4). (Total n = 48). d Schematic of endogenous short-term induction model. Mice were induced with DOX chow for 48 or 72 h and whole bone marrow was harvested for ex vivo analysis